Fertilizer synergist as well as preparation method and application thereof

Abstract

The invention belongs to the technical field of fertilizer preparation, and particularly discloses a fertilizer synergist as well as a preparation method and application thereof. The fertilizer synergist is prepared from the following raw materials in parts by weight: 50-70 parts of a multifunctional carrier, 4-8 parts of compound microorganism bacteria, 10-15 parts of a water-retaining agent and 0.5-2 parts of gamma-aminobutyric acid, the preparation method of the fertilizer synergist comprises the following steps: adding the multifunctional carrier into 4-10 parts of water, then carrying out high-temperature sterilization, cooling, then adding the compound microorganism bacteria, and fermenting at 30-36 DEG C for 1-4 days; and finally, adding the water-retaining agent and gamma-aminobutyric acid, and uniformly mixing. According to the fertilizer synergist provided by the invention, common substances are taken as raw materials, and the variety and the dosage are optimized, so that the preparation cost is controllable, the fertilizer efficiency is good, and the fertilizer synergist has a relatively good application prospect.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of fertilizer preparation, and particularly relates to a fertilizer synergist, a preparation method and application thereof. BACKGROUND

[0002] Food security is directly related to the foundation of China's economic and social development and is an important part of national security. Therefore, the status of cultivated land in China determines that China's agriculture must improve crop yield per unit and improve the quality of cultivated land to meet the increasing demand for various materials. In the cultivation of crops, the increase in the production and application amount of chemical fertilizers has promoted the increase in grain production in China; however, with the long-term application of fertilizers, some practical problems have emerged, such as low fertilizer utilization rate, nutrient leaching, unreasonable fertilization, and soil fertility decline, and therefore, the research and use of new fertilizers and related synergists are very necessary.

[0003] In the prior art, patent document CN110885278A discloses a new type of fertilizer synergist and a preparation method thereof, which comprises the following raw materials in parts by weight: urease inhibitor 2.1-6.5 parts, nitrification inhibitor 1.9-5.3 parts, composite microbial agent 1.7-5.3 parts, and water-retaining agent 0.8-2.3 parts. The above-mentioned new type of fertilizer synergist has good controlled release effect, can maintain fertilizer efficiency for a long time, improve the utilization rate of fertilizers, and promote crop growth; when applied to the planting process of gold orange, compared with the flower fertilizer without adding the fertilizer synergist, the fertilizer synergist can at least increase the plant height of gold orange potted plants by 64.17%, and at least increase the fruit setting rate of gold orange potted plants by 55.40%; when applied to eucalyptus special fertilizer, compared with the eucalyptus special fertilizer without adding the fertilizer synergist, the average tree height can be at least increased by 42.23%, and the average diameter at breast height can be at least increased by 29.60%. The above-mentioned synergist focuses on the slow-release effect, and the composite microbial agent is not specially treated, and the performance such as microbial activity cannot be fully satisfied.

[0004] For example, patent document CN108546210A discloses a fertilizer synergist, a fertilizer and a cotton planting method, which is composed of 1-5 mass parts of a water-retaining agent, 0.1-0.5 mass parts of dicyandiamide and 0.1-0.5 mass parts of graphene. The above technical solution provides a fertilizer synergist comprising a water-retaining agent, dicyandiamide and graphene, which can maintain soil moisture and prolong fertilizer efficiency, and can promote crop growth, especially the growth of cotton, and improve the weight of cotton seed. Experimental results show that the fertilizer synergist can significantly increase the weight of cotton seed. In the above components, the use of graphene material has a relatively high cost, which limits the widespread use of the fertilizer.

[0005] In view of the above problems, the present application is proposed. SUMMARY

[0006] In view of the deficiencies of the prior art, the present application aims to provide a fertilizer synergist, a preparation method and application thereof, which has good fertilizer efficiency and water retention and can effectively promote the planting quality of crops.

[0007] To achieve the above object, the present application adopts the following technical solution: In a first aspect, the present application provides a fertilizer synergist, which is prepared from the following raw materials in parts by weight: 50-70 parts of a multifunctional carrier, 4-8 parts of a composite microbial bacteria, 10-15 parts of a water-retaining agent, and 0.5-2 parts of gamma-aminobutyric acid.

[0008] As a preferred embodiment of the present application, the preparation of the multifunctional carrier comprises the following steps: S11, first washing and drying the aluminosilicate and then acid treating, then washing and drying, mixing with sodium hydroxide, high-temperature treatment, and finally grinding and sieving to obtain modified aluminosilicate; S12, mixing zeolite and sodium hydroxide, high-temperature treatment, then adding to ferrous sulfate solution for infiltration treatment, and calcination after treatment; after calcination, grinding and sieving to obtain modified zeolite; S13, adding chitosan to acetic acid solution, stirring uniformly, then adding the modified aluminosilicate obtained in step S11 and the modified zeolite obtained in step S12, and then heating and stirring; after treatment, washing and drying to obtain the multifunctional carrier.

[0009] As a preferred embodiment of the present application, in step S11, the acid treatment uses 0.6-1.2 mol / L hydrochloric acid solution, the treatment temperature is 40-60℃, and the treatment time is 0.5-4h; the amount ratio of aluminosilicate to hydrochloric acid solution is 1g:8-12mL; The mass ratio of aluminosilicate to sodium hydroxide is 1:0.4-0.6; The high-temperature treatment temperature is 370-390℃, and the treatment time is 0.5-2h; The grinding and sieving mesh size is 80-150 mesh.

[0010] As a preferred embodiment of the present application, in step S12, the mass ratio of zeolite to sodium hydroxide is 1:0.6-0.75; The high-temperature treatment temperature is 660-680℃, and the treatment time is 0.5-2h The amount ratio of zeolite to ferrous sulfate is 1g:5-10mL; The concentration of ferrous sulfate is 0.2-0.4mol / L; The infiltration treatment time is 12-24h; The calcination temperature is 720~750℃, and the calcination time is 0.5~2h; The grinding and sieving mesh size is 150~250 mesh.

[0011] As a preferred embodiment of the present invention, in step S13, the concentration of the acetic acid solution is 0.5~1.2wt%; the mass ratio of chitosan, acetic acid solution, modified attapulgite, and modified zeolite is 0.25~0.45:5~10:1:1.2~2.5. The heating and stirring process is carried out at a temperature of 40~60℃ for 2~6 hours.

[0012] As a preferred embodiment of the present invention, the preparation of the water-retaining agent includes the following steps: S21. Add attapulgite to hydrochloric acid solution, heat it, and then filter, wash and dry it to obtain pretreated attapulgite. S22. Add the pre-modified attapulgite obtained in step S21 to water, stir, then add polyvinyl alcohol, stir again, and then dry and calcine in sequence. After the treatment is completed, the modified attapulgite is obtained. S23. After washing, drying, and chopping the corn stalks, calcin them. After calcination, cool them to obtain corn stalks. S24. The corn stalks obtained in step S23 are added to a citric acid solution for heating treatment. After the treatment is completed, they are dried to obtain pretreated corn stalks. Subsequently, the obtained pretreated corn stalks are added to a potassium permanganate solution for impregnation. After impregnation, they are filtered, washed, and dried to obtain modified corn stalks. S25. After mixing the modified attapulgite clay obtained in step S22 and the modified corn stalks obtained in step S24 evenly, add them to water and then heat and stir. After the treatment is completed, filter, dry, grind and sieve to obtain a water-retaining agent.

[0013] As a preferred embodiment of the technical solution of the present invention, in step S21, the concentration of hydrochloric acid solution is 0.5~1mol / L; the ratio of attapulgite clay to hydrochloric acid solution is 1g:10~15mL; the heating treatment temperature is 30~45℃, and the treatment time is 0.5~4h. In step S22, the mass ratio of pre-modified attapulgite clay, water, and polyvinyl alcohol is 1:10~25:0.1~0.25; the calcination temperature is 310~330℃, and the calcination time is 30~120min. In step S23, the chopping length is 1~3cm; the calcination treatment is carried out under a nitrogen atmosphere at a temperature of 470~510℃ for 60~120min. In step S24, the concentration of citric acid solution is 0.5~1wt%; the ratio of corn stalk to citric acid solution is 1g:12~25mL; the heating temperature is 25~35℃, and the treatment time is 10~60min. The ratio of pretreated corn stalks to potassium permanganate solution is 1g: 5~12mL; the concentration of potassium permanganate solution is 0.05~0.15mol / L. The immersion temperature is room temperature, and the immersion time is 24~48 hours; In step S25, the mass ratio of modified attapulgite, modified corn stalks, and water is 1:1.5~2:30~50; the heating and stirring temperature is 35~45℃, the treatment time is 1~4h; and the grinding and sieving mesh is 80~150 mesh.

[0014] As a preferred embodiment of the technical solution of the present invention, the compound microbial strain is composed of soybean rhizobium and Bacillus in a mass ratio of 1:1.

[0015] Secondly, the present invention also provides a method for preparing the above-mentioned fertilizer synergist, comprising the following steps: Add the multifunctional carrier to 4-10 parts of water, then sterilize at high temperature. After cooling, add the compound microbial bacteria and ferment at 30-36℃ for 1-4 days. Finally, add the water-retaining agent and γ-aminobutyric acid, mix well, and it is ready.

[0016] Thirdly, this invention also provides the application of the aforementioned fertilizer synergist in crop cultivation. In practical applications, the aforementioned fertilizer synergist can be used directly, or it can be added to existing fertilizers for mixing and use.

[0017] Compared with the prior art, the present invention has the following beneficial effects: (1) The fertilizer synergist provided by the present invention, through the use of carrier, water-retaining agent, compound microbial bacteria and γ-aminobutyric acid, makes the prepared fertilizer synergist have good fertilizer effect and good water retention performance.

[0018] (2) The fertilizer synergist provided by this invention achieves good loading effect on compound microorganisms through the use of a multifunctional carrier. Specifically, the multifunctional carrier used in this invention uses attapulgite and zeolite as the main materials. Attachpulgite mainly uses interlayer adsorption, while zeolite mainly uses pore fixation. The combination of the two can achieve good immobilization of compound microorganisms, fully ensuring the fertilizer effect of the microbial community. In this invention, attapulgite is first acid-treated to remove pore impurities and expand the interlayer spacing. Then, it is subjected to high-temperature alkali treatment to further enrich its pore structure and expand the interlayer spacing, improving the immobilization efficiency of the microbial community. At the same time, the destruction of the lamellae exposes Si-OH / Al- The presence of OH active sites facilitates subsequent chitosan composite formation. High-temperature sodium hydroxide treatment of zeolite increases its specific surface area, promoting the adsorption of ferrous sulfate. Subsequent ferrous sulfate loading and calcination further improve the specific surface area of ​​the zeolite, enriching its porous structure and increasing the loading capacity for microorganisms. Simultaneously, the formation of iron on the surface allows for the introduction of iron as a trace element and enhances the surface activity of the zeolite, facilitating its composite formation with modified attapulgite and chitosan. The introduction of chitosan, acting as a mediator, improves the mutual composite formation of modified attapulgite and modified zeolite, while also enhancing the immobilization capacity for microorganisms.

[0019] The interaction of these three components helps to improve the immobilization and survival of microorganisms and enhance sustained release; at the same time, attapulgite, zeolite, and chitosan also have preliminary water-retention capabilities, helping to maximize the effectiveness of the water-retention agent.

[0020] (3) The fertilizer synergist provided by the present invention uses common attapulgite and biochar as raw materials, which are relatively common water-retaining substances. The present invention has carried out corresponding process treatments on them during use. Specifically, in the present invention, the attapulgite is treated with acid and polyvinyl alcohol. The purpose of acid treatment is to initially improve the adsorption capacity of attapulgite and its adsorption capacity for polyvinyl alcohol, thereby improving the calcination effect, enriching the pores, and improving the water retention effect. The biochar is made from common corn stalks. The biochar is first treated with citric acid to initially improve the porosity of the biochar, and then treated with potassium permanganate, which can further improve the pore structure, promote the improvement of water retention function, and introduce trace element manganese, which is beneficial to increase the active sites on the surface of biochar, improve the activity, and facilitate the compound use with attapulgite.

[0021] (4) The preparation process of the fertilizer synergist provided by the present invention is easy to implement.

[0022] In summary, the fertilizer synergist provided by this invention uses common substances as raw materials. By optimizing the types and dosages, the preparation cost is controllable, and the fertilizer effect is excellent, showing good application prospects. Detailed Implementation

[0023] The embodiments of the present invention are described in detail below. All embodiments are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0024] Unless otherwise specified, all chemical reagents and production equipment involved in this invention are purchased from the market.

[0025] The ratosite was purchased from Hubei Mingliu Ratosite Co., Ltd. The zeolite was purchased from Wuhu Honghuashan Zeolite Mining Co., Ltd. Chitosan was purchased from Weifang Kehai Chitosan Co., Ltd. Polyvinyl alcohol was purchased from Jinan Haipu Chemical Co., Ltd. Attapulgite clay was purchased from Mingguang Attapulgite Clay Material Factory in Anhui Province. The soybean rhizobium was purchased from Shanghai Jiachu Bioengineering Co., Ltd., product number SHBCCD11433; The Bacillus was purchased from Huawi Biotechnology, product number M50.

[0026] Furthermore, unless otherwise specified, all weight parts mentioned in this invention are mass parts, and the weight parts mentioned can be scaled up proportionally.

[0027] Example 1 A fertilizer enhancer, by weight, is prepared from the following raw materials: 60g of multifunctional carrier, 5g of compound microbial bacteria (a 1:1 mixture of soybean rhizobium and Bacillus), 12g of water-retaining agent, and 0.8g of γ-aminobutyric acid.

[0028] In this embodiment, the preparation of the multifunctional carrier includes the following steps: S11. The attapulgite is first washed and dried with water, then acid-treated with 0.8 mol / L hydrochloric acid solution (45℃, 2h). After treatment, it is washed and dried again, then mixed evenly with sodium hydroxide, followed by high-temperature treatment (385℃, 1h). Finally, it is ground and sieved through a 100-mesh sieve to obtain modified attapulgite. The ratio of attapulgite to hydrochloric acid solution is 1g:10mL; the mass ratio of attapulgite to sodium hydroxide is 1:0.45. S12. Zeolite and sodium hydroxide were mixed at a mass ratio of 1:0.65 and subjected to high-temperature treatment (670℃, 1h). After treatment, the mixture was added to a 0.28mol / L ferrous sulfate solution for impregnation (room temperature, 16h). After further treatment, the mixture was calcined (725℃, 0.5h). After calcination, the mixture was ground and sieved through a 200-mesh sieve to obtain modified zeolite. S13. Chitosan is added to a 0.8 wt% acetic acid solution and stirred until homogeneous. Then, the modified attapulgite obtained in step S11 and the modified zeolite obtained in step S12 are added separately. The mixture is then heated and stirred (40°C, 3 h). After the treatment is completed, the mixture is washed and dried to obtain a multifunctional carrier. The mass ratio of chitosan, acetic acid solution, modified attapulgite, and modified zeolite is 0.3:8:1:1.5.

[0029] In this embodiment, the preparation of the water-retaining agent includes the following steps: S21. Add attapulgite to a 0.9 mol / L hydrochloric acid solution at a ratio of 1 g: 12 mL, heat (40 °C, 2 h), then filter, wash, and dry to obtain pretreated attapulgite. S22. Add the pre-modified attapulgite obtained in step S21 to water, stir, then add polyvinyl alcohol, stir again, and then dry and calcine (320℃, 40min) in sequence. After the treatment is completed, modified attapulgite is obtained; wherein, the mass ratio of pre-modified attapulgite, water and polyvinyl alcohol is 1:12:0.15. S23. After washing, drying, and chopping the corn stalks (about 1 cm), calcine them (nitrogen atmosphere, 480℃, 80 min). After calcination, cool them to obtain corn stalks. S24. The corn stalks obtained in step S23 are added to a 0.6 wt% citric acid solution and heated (30℃, 30 min). After treatment, they are dried to obtain pretreated corn stalks. Subsequently, the pretreated corn stalks are added to a 0.1 mol / L potassium permanganate solution for impregnation (room temperature, 36 h). After impregnation, they are filtered, washed, and dried to obtain modified corn stalks. The ratio of corn stalks to citric acid solution is 1 g: 20 mL; the ratio of pretreated corn stalks to potassium permanganate solution is 1 g: 8 mL. S25. After mixing the modified attapulgite clay obtained in step S22 and the modified corn stalks obtained in step S24 evenly, add them to water and then heat and stir (40℃, 2h). After the treatment is completed, filter, dry, grind and sieve through 100 mesh to obtain a water-retaining agent. The mass ratio of modified attapulgite clay, modified corn stalks and water is 1:1.5:40.

[0030] In this embodiment, a method for preparing the above-mentioned fertilizer synergist is also provided, comprising the following steps: Add the multifunctional carrier to 6g of water, then sterilize at high temperature. After cooling, add the compound microbial bacteria and ferment at 32℃ for 2 days. Finally, add the water-retaining agent and γ-aminobutyric acid, mix well, and it is ready.

[0031] Example 2 A fertilizer synergist, by weight, is prepared from the following raw materials: 65g of multifunctional carrier, 5.5g of compound microbial bacteria (a 1:1 mixture of soybean rhizobium and Bacillus), 11g of water-retaining agent, and 0.8g of γ-aminobutyric acid.

[0032] In this embodiment, the preparation of the multifunctional carrier includes the following steps: S11. The attapulgite is first washed and dried with water, then acid-treated with 0.85 mol / L hydrochloric acid solution (45℃, 2.5h). After treatment, it is washed and dried again, then mixed evenly with sodium hydroxide, followed by high-temperature treatment (380℃, 1.5h). Finally, it is ground and sieved through a 100-mesh sieve to obtain modified attapulgite. The ratio of attapulgite to hydrochloric acid solution is 1g:10mL; the mass ratio of attapulgite to sodium hydroxide is 1:0.5. S12. Zeolite and sodium hydroxide were mixed at a mass ratio of 1:0.6 and subjected to high-temperature treatment (675℃, 1h). After treatment, the mixture was added to a 0.28mol / L ferrous sulfate solution for impregnation (room temperature, 18h). After further treatment, the mixture was calcined (730℃, 0.5h). After calcination, the mixture was ground and sieved through a 200-mesh sieve to obtain modified zeolite. S13. Chitosan is added to a 0.8 wt% acetic acid solution and stirred until homogeneous. Then, the modified attapulgite obtained in step S11 and the modified zeolite obtained in step S12 are added separately. The mixture is then heated and stirred (40°C, 3 h). After the treatment is completed, the mixture is washed and dried to obtain a multifunctional carrier. The mass ratio of chitosan, acetic acid solution, modified attapulgite, and modified zeolite is 0.3:8:1:1.6.

[0033] In this embodiment, the preparation of the water-retaining agent includes the following steps: S21. Add attapulgite to a 0.9 mol / L hydrochloric acid solution at a ratio of 1 g: 15 mL, heat (40 °C, 2 h), then filter, wash, and dry to obtain pretreated attapulgite. S22. Add the pre-modified attapulgite obtained in step S21 to water, stir, then add polyvinyl alcohol, stir again, and then dry and calcine (325℃, 30min) in sequence. After the treatment is completed, modified attapulgite is obtained; wherein, the mass ratio of pre-modified attapulgite, water and polyvinyl alcohol is 1:12:0.16. S23. After washing, drying, and chopping the corn stalks (about 1 cm), calcine them (nitrogen atmosphere, 485℃, 70 min). After calcination, cool them to obtain corn stalks. S24. The corn stalks obtained in step S23 are added to a 0.6 wt% citric acid solution and heated (30°C, 30 min). After treatment, they are dried to obtain pretreated corn stalks. Subsequently, the pretreated corn stalks are added to a 0.1 mol / L potassium permanganate solution for impregnation (room temperature, 36 h). After impregnation, they are filtered, washed, and dried to obtain modified corn stalks. The ratio of corn stalks to citric acid solution is 1 g: 18 mL; the ratio of pretreated corn stalks to potassium permanganate solution is 1 g: 8 mL. S25. After mixing the modified attapulgite clay obtained in step S22 and the modified corn stalks obtained in step S24 evenly, add them to water and then heat and stir (40℃, 2h). After the treatment is completed, filter, dry, grind and sieve through 100 mesh to obtain a water-retaining agent. The mass ratio of modified attapulgite clay, modified corn stalks and water is 1:1.5:40.

[0034] In this embodiment, a method for preparing the above-mentioned fertilizer synergist is also provided, comprising the following steps: Add the multifunctional carrier to 5.5g of water, then sterilize at high temperature. After cooling, add the compound microbial bacteria and ferment at 32℃ for 2 days. Finally, add the water-retaining agent and γ-aminobutyric acid, mix well, and it is ready.

[0035] Example 3 A fertilizer synergist, by weight, is prepared from the following raw materials: 55g multifunctional carrier, 4.8g compound microbial bacteria (a 1:1 mixture of soybean rhizobium and Bacillus), 12.5g water-retaining agent, and 0.9g γ-aminobutyric acid.

[0036] In this embodiment, the preparation of the multifunctional carrier includes the following steps: S11. The attapulgite is first washed and dried with water, then acid-treated with 0.8 mol / L hydrochloric acid solution (45℃, 2h). After treatment, it is washed and dried again, then mixed evenly with sodium hydroxide, followed by high-temperature treatment (390℃, 0.5h), and finally ground and sieved through 100 mesh to obtain modified attapulgite. The ratio of attapulgite to hydrochloric acid solution is 1g:10mL; the mass ratio of attapulgite to sodium hydroxide is 1:0.45. S12. Zeolite and sodium hydroxide were mixed at a mass ratio of 1:0.68 and subjected to high-temperature treatment (675℃, 1h). After treatment, the mixture was added to a 0.28mol / L ferrous sulfate solution for impregnation (room temperature, 16h). After further treatment, the mixture was calcined (720℃, 0.5h). After calcination, the mixture was ground and sieved through a 200-mesh sieve to obtain modified zeolite. S13. Chitosan is added to a 0.8 wt% acetic acid solution and stirred until homogeneous. Then, the modified attapulgite obtained in step S11 and the modified zeolite obtained in step S12 are added separately. The mixture is then heated and stirred (40°C, 3 h). After the treatment is completed, the mixture is washed and dried to obtain a multifunctional carrier. The mass ratio of chitosan, acetic acid solution, modified attapulgite, and modified zeolite is 0.3:9:1:1.7.

[0037] In this embodiment, the preparation of the water-retaining agent includes the following steps: S21. Add attapulgite to a 0.85mol / L hydrochloric acid solution at a ratio of 1g:12mL, heat (40℃, 2h), then filter, wash, and dry to obtain pretreated attapulgite. S22. Add the pre-modified attapulgite obtained in step S21 to water, stir, then add polyvinyl alcohol, stir again, and then dry and calcine (325℃, 40min) in sequence. After the treatment is completed, modified attapulgite is obtained; wherein, the mass ratio of pre-modified attapulgite, water and polyvinyl alcohol is 1:12:0.16. S23. After washing, drying, and chopping the corn stalks (about 1 cm), calcine them (nitrogen atmosphere, 480℃, 80 min). After calcination, cool them to obtain corn stalks. S24. The corn stalks obtained in step S23 are added to a 0.6 wt% citric acid solution and heated (30°C, 30 min). After treatment, they are dried to obtain pretreated corn stalks. Subsequently, the pretreated corn stalks are added to a 0.1 mol / L potassium permanganate solution for impregnation (room temperature, 36 h). After impregnation, they are filtered, washed, and dried to obtain modified corn stalks. The ratio of corn stalks to citric acid solution is 1 g: 20 mL; the ratio of pretreated corn stalks to potassium permanganate solution is 1 g: 9 mL. S25. After mixing the modified attapulgite clay obtained in step S22 and the modified corn stalks obtained in step S24 evenly, add them to water and then heat and stir (40℃, 2h). After the treatment is completed, filter, dry, grind and sieve through 100 mesh to obtain a water-retaining agent. The mass ratio of modified attapulgite clay, modified corn stalks and water is 1:1.5:40.

[0038] In this embodiment, a method for preparing the above-mentioned fertilizer synergist is also provided, comprising the following steps: Add the multifunctional carrier to 6.5g of water, then sterilize at high temperature. After cooling, add the compound microbial bacteria and ferment at 32℃ for 2 days. Finally, add the water-retaining agent and γ-aminobutyric acid, mix well, and it is ready.

[0039] Comparative Example 1 Compared with Example 1, the treatment of ferrous sulfate solution in step S12 was omitted in Comparative Example 1, but all other steps were the same.

[0040] Comparative Example 2 Compared with Example 1, the use of chitosan in step S13 was omitted in Comparative Example 2, but all other steps were the same.

[0041] Comparative Example 3 Compared with Example 1, the addition of polyvinyl alcohol in step S22 was omitted in Comparative Example 3, but all other steps were the same.

[0042] Comparative Example 4 Compared with Example 1, the treatment of potassium permanganate solution in step S24 was omitted in Comparative Example 4, but all other steps were the same.

[0043] Next, the fertilizer synergists prepared in Example 1 and Comparative Examples 1-4 were compared in their effects on pea cultivation. The specific method is as follows: Suitable fields (uniform fertility, flatness, etc.) were selected and divided into 6 equal plots. The same variety of peas was randomly planted in each plot, and ordinary fertilizer (nitrogen, phosphorus, and potassium ratio of 2.9:1:1.8) was applied to all plots. Five plots were also treated with 10% of the fertilizer synergist (i.e., Example 1 and Comparative Examples 1-4) of the ordinary fertilizer. The remaining plot was left untreated. Other planting methods were consistent with existing technologies (such as tillage, planting density, spraying, irrigation, etc.). Each plot was divided into 3 sub-plots, and the pea yield and other parameters were summed and averaged. Soil conditions and moisture content were measured at the same time. The planting results are shown in Table 1.

[0044] Table 1 Planting Results As can be seen from Table 1, the fertilizer synergist provided by the present invention can greatly promote the yield of peas, maintain good soil conditions for planting, and is suitable for continuous cultivation; it also has a good water retention effect.

[0045] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A fertilizer synergist, characterized in that, It is prepared by weight from the following raw materials: 50-70 parts of multifunctional carrier, 4-8 parts of compound microbial bacteria, 10-15 parts of water-retaining agent, and 0.5-2 parts of γ-aminobutyric acid.

2. The fertilizer synergist according to claim 1, characterized in that, The preparation of the multifunctional carrier includes the following steps: S11. The attapulgite is first washed and dried with water, then acid treated. After the treatment, it is washed and dried again, then mixed evenly with sodium hydroxide, then treated at high temperature, and finally ground and sieved to obtain modified attapulgite. S12. The zeolite and sodium hydroxide are mixed and subjected to high-temperature treatment. After the treatment, the mixture is added to a ferrous sulfate solution for wetting treatment. After the treatment, the mixture is calcined. After calcination, the mixture is ground and sieved to obtain the modified zeolite. S13. Add chitosan to acetic acid solution, stir evenly, then add the modified attapulgite obtained in step S11 and the modified zeolite obtained in step S12 respectively, and then heat and stir. After the treatment is completed, wash and dry to obtain a multifunctional carrier.

3. The fertilizer synergist according to claim 2, characterized in that, In step S11, the acid treatment is carried out using a 0.6~1.2mol / L hydrochloric acid solution at a temperature of 40~60℃ for 0.5~4h; the ratio of attapulgite to hydrochloric acid solution is 1g:8~12mL. The mass ratio of attapulgite to sodium hydroxide is 1:0.4~0.6; The high-temperature treatment temperature is 370~390℃, and the treatment time is 0.5~2h; The grinding and sieving mesh size is 80~150 mesh.

4. A fertilizer synergist according to claim 2, characterized in that, In step S12, the mass ratio of zeolite to sodium hydroxide is 1:0.6~0.75; The high-temperature treatment temperature is 660~680℃, and the treatment time is 0.5~2h; The ratio of zeolite to ferrous sulfate is 1g: 5~10mL; The concentration of ferrous sulfate is 0.2~0.4 mol / L; The soaking time is 12~24h; The calcination temperature is 720~750℃, and the calcination time is 0.5~2h; The grinding and sieving mesh size is 150~250 mesh.

5. A fertilizer synergist according to claim 2, characterized in that, In step S13, the concentration of the acetic acid solution is 0.5~1.2wt%; the mass ratio of chitosan, acetic acid solution, modified attapulgite, and modified zeolite is 0.25~0.45:5~10:1:1.2~2.

5. The heating and stirring process is carried out at a temperature of 40~60℃ for 2~6 hours.

6. A fertilizer synergist according to claim 1, characterized in that, The preparation of the water-retaining agent includes the following steps: S21. Add attapulgite to hydrochloric acid solution, heat it, and then filter, wash and dry it to obtain pretreated attapulgite. S22. Add the pre-modified attapulgite obtained in step S21 to water, stir, then add polyvinyl alcohol, stir again, and then dry and calcine in sequence. After the treatment is completed, the modified attapulgite is obtained. S23. After washing, drying, and chopping the corn stalks, calcin them. After calcination, cool them to obtain corn stalks. S24. The corn stalks obtained in step S23 are added to a citric acid solution and heated. After the treatment is completed, they are dried to obtain pretreated corn stalks. Subsequently, the obtained pretreated corn stalks were added to a potassium permanganate solution for soaking. After soaking, the stalks were filtered, washed, and dried to obtain modified corn stalks. S25. After mixing the modified attapulgite clay obtained in step S22 and the modified corn stalks obtained in step S24 evenly, add them to water and then heat and stir. After the treatment is completed, filter, dry, grind and sieve to obtain a water-retaining agent.

7. A fertilizer synergist according to claim 6, characterized in that, In step S21, the concentration of hydrochloric acid solution is 0.5~1mol / L; the ratio of attapulgite clay to hydrochloric acid solution is 1g:10~15mL; the heating treatment temperature is 30~45℃, and the treatment time is 0.5~4h. In step S22, the mass ratio of pre-modified attapulgite clay, water, and polyvinyl alcohol is 1:10~25:0.1~0.25; the calcination temperature is 310~330℃, and the calcination time is 30~120min. In step S23, the chopping length is 1~3cm; the calcination treatment is carried out under a nitrogen atmosphere at a temperature of 470~510℃ for 60~120min. In step S24, the concentration of citric acid solution is 0.5~1wt%; the ratio of corn stalk to citric acid solution is 1g:12~25mL; the heating temperature is 25~35℃, and the treatment time is 10~60min. The ratio of pretreated corn stalks to potassium permanganate solution is 1g: 5~12mL; the concentration of potassium permanganate solution is 0.05~0.15mol / L. The immersion temperature is room temperature, and the immersion time is 24~48 hours; In step S25, the mass ratio of modified attapulgite, modified corn stalks, and water is 1:1.5~2:30~50; the heating and stirring temperature is 35~45℃, the treatment time is 1~4h; and the grinding and sieving mesh is 80~150 mesh.

8. A fertilizer synergist according to claim 1, characterized in that, The compound microbial strain is composed of soybean rhizobium and Bacillus in a mass ratio of 1:

1.

9. A method for preparing the fertilizer synergist according to any one of claims 1 to 8, characterized in that, Includes the following steps: Add the multifunctional carrier to 4-10 parts of water, then sterilize at high temperature. After cooling, add the compound microbial bacteria and ferment at 30-36℃ for 1-4 days. Finally, add the water-retaining agent and γ-aminobutyric acid, mix well, and it is ready.

10. The application of the fertilizer synergist according to any one of claims 1 to 8 in crop cultivation.

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